In the construction and finishing trades there have been many prior attempts to simulate a brick, stone or tile surface using materials less expensive than the genuine material. Some of these attempts involved cutting the genuine brick, stone, etc. into thin slabs which are then adhered to a conventional concrete wall, etc. for support. See, for example, U.S. Pat. Nos. 3,131,514; 1,669,351; 3,660,214; 3,740,910; 3,521,418; 3,775,916; 3,646,715; 2,122,696; 2,149,784; 2,339,489; 3,426,490; and 1,902,271. The expense, time, and care involved in cutting the brick or stone, etc. into desired thin slabs and then adhering them to the desired surface or substrate detract from the advantages of such techniques.
Another attempt to simulate a brick, stone, tile, etc. exterior involves pouring a mortar or concrete mix into a mold or form which includes the desired relief, e.g., brick, stone, etc. This technique is described, for example, in U.S. Pat. Nos. 3,002,322 and 3,874,140. Various limitations are inherent in this technique. For example, in order for the concrete or mortar mix to properly and completely fill the molds without leaving air pockets the mix must contain a considerable amount of water. This detracts from the strength of the cured mixture and increases the curing time. The finished product unfortunately still has the appearance of concrete and is all the same color, i.e., it does not have one color for the bricks or stone relief and a different color for the spacing between the brick or stone shapes. Moreover, it is difficult if not impossible to obtain sharp edges on the brick or stone shapes in these molds. As a result, the shapes are not as realistic as desired.
Another technique simply involved making panels or sections from plastic which has been molded to the desired relief. The panels or sections are then used as the outer decorative facing for the structure to be covered. See, for example, U.S. Pat. Nos. 3,882,218; 3,177,279; and 3,232,017. Of course, these products do not provide a totally realistic appearance and would not be adequate as a substitute for real brick, stone, tile, etc. in all situations.
Still another technique involved making simulated brick or tile elements out of plastic and then bonding them to a supporting panel or sheet with adhesive. See U.S. Pat. Nos. 3,991,529 and 4,079,554. Again, such a technique includes serious limitations.
Yet another technique involved forming two layers of magnesite applied to a metal lathe. The second layer is of a different color than the first layer. Before the second layer hardens, grooves are cut therethrough to form the shape of bricks, for example, and to reveal the underlying layer of magnesite. See U.S. Pat. No. 1,583,748.
Another cumbersome technique described in U.S. Pat. No. 3,426,490 involves forming individual brick veneer blocks made of concrete or fired clay which are adhered to a wire mesh in panel form. The panels are then secured to a wall with nails or staples. Mortar is then applied between the veneer blocks and forced into the wire mesh.
U.S. Pat. No. 3,496,694 describes yet another method in which molded formations made from cementitious plaster, plastic, or other suitable decorative material are adhered to a flexible base material. The prefabricated material may then be rolled up and transported to the job site where it is attached to the frame of a building.
U.S. Pat. No. 3,868,801 describes a building panel for a prefabricated house. The panel includes masonry elements (such as bricks), polyester mortar, wire mesh, polymer foam, and inner facing layers are held together by the mortar and foam.
U.S. Pat. No. 3,344,570 describes a reinforced flooring tile including a body of concrete with reinforcing framework embedded therein. The network is thermoplastic synthetic resin or metallic reinforcing.
U.S. Pat. No. 3,067,545 describes an artificial siding for frame buildings. A brick-like block is made of standard concrete block mixture which may include coloring pigments and water-proofing agents. The block is molded on metal mesh in such a manner that it extends through the mesh. The exterior surface of the walls of the building are covered with wooden sheathing and then felt paper. The brick/mesh pieces are then nailed to the wall individually as siding in such a manner that the mesh overlaps the mesh of the piece in the row below it. Presumably the spaces between adjacent bricks would have to be sealed in some manner
U.S. Pat. No. 2,819,495 describes a method for making building blocks having a molded mortar surfacing simulating a plurality of bricks or stones. The mortar is first placed into a mold and must be tamped into compartments; then additional intermediate layers are added, after which concrete mix is added to form the main portion of the block. A disadvantage of this technique is that the facing is applied to the concrete block prior to the required conventional steam or oven curing of the block. Accordingly, additional care is required to handle such blocks prior to curing.
U.S. Pat. No. 2,748,443 describes a particular technique (involving a specially designed stencil) for applying a plastic mix, like mortar, to the face of a building in a predetermined pattern to simulate stone blocks. However, the wall to be faced is first covered with lathing over which is provided a continuous coating of plastic mix and then a brown coat. Then the mortar mix is applied with the aid of the stencil. This technique, of course, would not be practical for use with individual building blocks, nor is it a convenient technique even for large building faces.
U.S. Pat. No. 1,571,849 describes a multi-step method for making building blocks which is similar to that described in U.S. Pat. No. 2,819,495. A grate is placed on a flat plate and a concrete mix is then placed into the openings in the grate and must be tamped down until it is even with the top of the grate. The grate is then removed and the spaces between the shapes formed by the grate are filled with cementitious compost colored differently than the shapes left by the grate. Then another concrete mixture is added to form another layer. The resulting structure is then removed from the mold on the flat plate and placed in the bottom of a mold of a cement block forming machine where the main portion of a cement block is formed on top.
U.S. Pat. No. 2,618,815 describes a rather involved and tedious method for applying a coating of plaster or cement to a wall to simulate the appearance of stone, cement blocks, or similar construction units. A plastic mold is filled with a concrete and mortar mix. The mold is then placed against a wall until the mortar mix adheres and sets (may be of the order of three hours). Alternatively, the mold may be coated with an adhesive coating such as a mixture of paraffin and kerosene. Marble dust, quartz particles or the like are then spread onto the coating, followed by ground stone particles. The mold is then filled with the mortar mix. Then the mortar mix may be pressed against the wall and the mold removed immediately, leaving the marble dust and paraffin-kerosene coating covering the mortar.
U.S. Pat. No. 2,130,911 describes a prefabricated building unit in which a first layer is applied directly onto a Celotex, fiber board, etc. The first layer may be plaster or cement (0.25 to 2 inches thick). Then facing elements made from natural stone, cement, wood, metal, linoleum or the like are pressed onto the surface of the first layer while either or both are in a plastic or semi-cured condition. Alternatively, the facing elements may be secured to the first layer by cement or adhesive. The facing elements may be pre-formed or may be formed from a plastic material on the base member in a continuous operation.
U.S. Pat. No. 3,304,673 describes a pre-cast panel which is adapted to be keyed to adjacent panels with specially formed inserts. The panel includes a base layer of cement and an embossed outer layer which simulates brick. Before the base layer is set the outer layer is added and then a mold is impressed against the surface of the outer layer to emboss it and provide a simulated brick facing. The outer layer may include pigments for coloring. Alternatively, the outer layer may be cast in a separate mold, hardened, and then laid in place over the first layer.